The present invention relates to hinges and more particularly pertains to a shaftless hinge and its manufacturing method.
Hinges serve as an intermediate member to movably articulate a connecting piece with another. They have wide spectrum of usage, such as to connect doors, windows, cabinets, boxes and others.
At present, there are various types of hinges. FIG. 1 shows the hinge structure of one typical type. It comprises two hinge plates 1; two or more shaft bushes 2 are disposed on the confronting sides of the two hinge plates 1; the plurality of shaft bushes 2 of the two hinge plates 1 are coaxially disposed and alternate with each other; by inserting a shaft 3 through the shaft bushes 2, the two hinge plates 2 are movably articulated; shaft caps are generally disposed at the two ends of the shaft 3 to secure the shaft in the shaft bushes; this type of hinge has simple structure and is easy to use and install and has high applicability, but it also has obvious disadvantages: (1) The shaft 3 and the hinge plates 1 are independent components. The shaft caps at the ends of the shaft 3 may fall off due to abrasion and rusting with passage of time. The shaft is also easy to fall off and therefore affect the usage of the hinge and even cause accidents; (2) The contact surfaces of the exterior surface of the shaft 3 and the interior surface of the shaft bushes 2 may be abraded and rusted, forming an oxidizing layer. The oxidizing layer will fall off with the vibration and movement of the hinge and the diameter of the shaft 3 gradually reduces. This widens the gap between the shaft 3 and the shaft bushes 2 so that radial displacement occurs between the shaft bushes 2 and the shaft 3. This affects the rotation of the hinge and the operation of the product; (3) The manufacturing of conventional shaft hinges must include a riveting procedure and the manufacturing process is relatively complex and the manufacturing costs are therefore increased; (4) The manufacturing of conventional hinges generally requires manual assembling after the shaft 3 and the hinge plates 1 are produced (i.e. to align the two hinge plates 1 and insert the shaft 3 into the shaft bushes 2 of the hinge plates 1. The assembling process is relatively complex, leading to low production efficiency and increased costs.
U.S. Pat. No. 5,127,132A discloses a “Hinge made from identical hinge plates”. This hinge does not have a complete shaft. The two hinge plates have identical structure comprising four hollow coaxially disposed tubular barrels, two of which are disposed with coaxial bores and the other two are disposed with cylindrical projections at their ends. When the two hinge plates are assembled, the two cylindrical projections of one hinge plate are inserted into the coaxial bores of the other hinge plate, forming an articulated hinge. This hinge is substantially a shaftless hinge and can overcome the disadvantages of conventional hinges with shafts. However, it also has obvious shortcomings: Since tubular barrels with cylindrical projections and tabular barrels with bores have to be manufactured to each hinge plate, the structure of the hinge is relative complex and processing and assembling are quite complicated and inconvenient.